The present invention relates to an electronic musical instrument utilizing an artificial or electronic sound source of a physical model simulating the sound mechanism of an acoustic musical instrument.
There has been known conventional electronic musical instruments of the keyboard type provided with a plurality of keys. In such electronic keyboard instruments, the player depresses keys to input performance information such as key code, initial touch and after touch. The electronic musical instrument has therein an electronic sound source directly receiving the performance information so as to form musical tones to be sounded as well a to effect modulation thereof.
On the other hand, there has been known an electronic sound source of a physical model which is composed of an electronic circuitry constructed to physically simulate the mechanical vibration system of an acoustic stringed instrument in order to generate continuous musical sounds analogous to, for example, violin performance. Such physical model sound source is disclosed, for example, in U.S. Pat. No. 4,984,276. In such a system, the instrument receives tone pitch information and performance information associated with bowing force and bowing velocity which represent bow manipulation in playing of an acoustic stringed instrument such as violin. The system operates according to the inputted information to generate musical sounds. The performance information of the physical model is manually inputted by the player to vary parameters or so called physical image such as bowing force and bowing velocity so as to sophisticatedly and naturally control musical tone volume and color in an analogous manner of the acoustic instrument according to the input performance even after initiation of the continuous sound generation.
As described, the physical model sound source synthesizes musical tones to simulate a sound generation mechanism of the acoustic musical instrument, hence the sound source must receive the physical model performance information which accurately represents the manner of manual playing. However, the typical performance tool or implement such as a keyboard can only input specified performance information pertinent to key operation. Since the keyboard is originally used as a operation implement for striking type of the stringed instrument, the keyboard mechanism is inconvenient in use as an input implement for sustained sound generation type or bowing type of the stringed instrument.
Generally, the keyboard is not suitable functionally for controlling a sustained music tone. In spite of such drawbacks or inconvenience, since the keyboard is usually installed in various types of the electronic musical instruments, the keyboard is necessarily used even for performing musics composed of sustained tones.